Speed control device

ABSTRACT

D R A W I N G A SPEED CONTROL DEVICE FOR A MOTOR VEHICLE INCLUDES AN ELECTRICALLY ACTUATED THROTTLE OPERATOR CONTROLLED BY SPEED SENSITIVE ELECTRICAL CIRCUITRY. THE CIRCUITRY INCLUDES A SPEEDOMETER DRIVEN ELECTRICAL GENERATOR FOR SENSING VEHICLE SPEED AS A FUNCTION OF REACTION TORQUE, A VARIABLE RESISTANCE CONNECTED TO THE GENERATOR FOR SELECTING A DESIRED SPEED, A MANUALLY OPERATED PUSH BUTTON FOR PLACING THE DEVICE IN OPERATION, EMPLOYS THE VEHICLE BRAKE LIGHT CIRCUIT FOR OPERATION, AND EMPLOYS THE VEHICLE BRAKE LIGHT CIRCUIT FOR REMOVING THE DEVICE FROM OPERATION.

Feb. 23, 1971 c. D. FOX

SPEED CONTROL DEVICE V 3 Sheets-Sheet 1v Original Filed Nov.. 27, 1964 mww 7 7 li i- II/IIIIIIIII/l III/I4 'IIIIIIII/I/I VII/IIII/I/I/I/A II b'II/III/III/l INVENTOR (6 171'0'112,

Feb. 23, 1971 c. D. FOX Re; 7,070

ISPEED bONTROL DEVICE Original FilediNov 27, 1964 I s Sheets-Sheet 2 CZi r 62* i 42 -5 2 I I 4 416a mu E" g i l 411 I J N 62 g I m 15 4 INVETOR 66 Llararzcafl iaz.

ATTORNEY.

Feb. 23, 1971 c. D. FOX

SPEED CONTROL DEVICE 3 Sheets-Shee t 5 Original Filed-Nov. 27, 1964 I QINVENTCII Clarence Fax,

ATTORNEY United States Patent 27,070 SPEED CONTROL DEVICE Clarence D.Fox, Decatur, Ill., assignor to Borg-Warner Corporation, Chicago, 11].,a corporation of Illinois Original No. 3,297,104, dated Jan. 10, 1967,Ser. No.

414,124, Nov. 27, 1964. Application for reissue Jan. 22,

1968, Ser. No. 746,715

Int. Cl. B60k 31/00 US. Cl. 180-409 13 Claims Matter enclosed in heavybrackets appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade bv reissue.

ABSTRACT OF THE DISCLOSURE A speed control device for a motor vehicleincludes an electrically actuated throttle operator controlled by speedsensitive electrical circuitry. The circuitry includes a speedometerdriven electrical generator for sensing vehicle speed as a function ofreaction torque, a variable resistance connected to the generator forselecting a desired speed, a manually operated push button for placingthe device in operation, and employs the vehicle brake light circuit forremoving the device from operation.

This invention relates to a speed control device and, in particular, aspeed control device for maintaining the speed of a prime mover such asthat for an automotive vehicle without requiring an operator to regulatethe speed output of such a prime mover by the usual accelerator means.

There have been previously proposed devices or mechanisms forcontrolling and maintaining a manually selected speed of a prime moversuch as that for a vehicle of the automotive type or the like, withoutrequiring the operator to control such speed by constant operation ofthe usual vehicle accelerator pedal. Most of the systems have beenrelatively complicated in structure, resulting in a high initial costand high maintenance expense due to the complexity and the sensitivityof such previously available systems.

It is still a more detailed object of this invention to provide aneconomically and commercially practicable improved automatic speedcontrol device that is relatively simple in its structure and automaticin its operation.

Another object of this invention is to provide an improved speed controldevice that is effective to automatically assume control of the fueldelivery to a prime mover of a vehicle after the vehicle has beenaccelerated to a predetermined speed setting.

Another object of this invention is to provide a device of the presenttype that incorporates improved means for adjustment effective to sensechanges in load conditions and prevent under-speed and over-speedconditions of the prime mover and which is effective to make correctionsfor bringing the prime mover to a pre-set output speed.

It is still a more detailed object of this invention to provide animproved speed control device which includes means forming an electricalgenerator adapted to be driven by the speedometer cable. This generatoris particularly characterized by having an arcuately movable reactionstator effective to operate a uniquely arranged control switch, rheostatmeans are arranged to be selectively set in accordance with the chosenvehicle speed for regulating the current delivered by the generator as afunction of the vehicle speed-setting to effect the operation of thecontrol switch when the selected speed has been reached to in turncontrol the fuel delivery of the prime mover.

Still another object of this invention is to provide an "ice improvedspeed control or selectable speed maintaining device provided with apair of electrical contacts operable in accordance with vehicle sensingmeans and controlled by a speed selector rheostat means whereby theelectrical generating means provides arcuate motion for impartingrelative movement to the electrical contacts toward and away from oneanother and completing the electrical circuit and opening the circuitagainst the action of a spring biasing means.

These and other objectives of the invention will become more readilyapparent from reference to the following description and appendeddrawings to wit:

FIG. 1 is a schematic view of the invention;

FIG. 2 is a view partly in section of the invention illustrating theelectrical generator and torque reaction sensing means forming anessential part of the unique governor;

FIGS. 2a and 2b are enlarged sectional views of the eccentric cam meansshown in FIG. 2;

FIG. 3 is a sectional view taken substantially along line 33 of FIG. 2;

FIG. 4 is a sectional view of a modification of the form of theinvention shown in FIG. 3.

In the basic essentials, the present invention comprises means formaintaining the speed of a vehicle at a manually pre-selected valueirrespective of the variations in the surface grade over which thevehicle is being driven. In the present preferred embodiment, anelectrical current generator G is employed and driven from thespeedometer cable to thus generate a current which is a function of thespeed of the vehicle. The rotating armature A or 12 (FIG. 2) of thegenerator moves in the field of a permanent magnet M of an arcuatelymovable stator S and develops an opposing magnetic field with aresultant electric current being generated that is regulated by amanually adjustable rheostat R by which the value of the currentsupplied is predetermined and which settings of the rheostat arecorrelated to the various speeds of the vehicle which speeds are to beselectively maintained. Hence, the reaction of the stator S of thegenerator G will be a direct function of the speed of rotation of thegenerator driven in the present instance by the speedometer cable and ofthe setting of the rheostat R. The stator S of the generator G is madeto be arcuately adjustable againstthe resistance of a biasing spring [B]N and will reflect in its reaction the intensity of the magnetic fieldproduced by the current passing through the armature A or 12 and therate of rotation of the armature. By opening and closing a pair ofcontrol contacts 01 and C2, one of which is operated by the arcuatelyadjustable stator, there is thus provided means for accurately sensingwhen the vehicle has reached a predetermined selected speed. It thenbecomes a simple matter to employ the opening and closing of thesecontacts C1 and C2 to automatically control the delivery of fuel to theprime mover. This is accomplished in the present embodiment by havingthe generator-operated contacts remain closed below the selected speedcausing the fuel delivery means to be maintained open until thepredetermined selected speed has been reached, whereupon the opening ofthe contacts by the reaction movement of the stator S becomes effectiveto reduce the delivery of fuel to the prime mover until and when thespeed of the vehicle drops below said selected value.

While these basic essentials are comprehended in the broader scope ofthe present invention, it will be understood that in its more specificaspects the invention comprehends certain additional and importantfeatures. One of these more refined features is the provision of [a] aneccentric modulating means [E] E for adjusting the position of one ofthe generator contacts with refer met: to the other contact at afrequency corresponding the speed of rotation of the armature A or 12which tssures added smoothness to the operation of the fuel leliverymeans as will appear. Still another more specific tspect of theinvention is the provision of a centrifugaly operated switch meanshaving contacts C3, 04 effective .0 maintain the control circuit to thespeed maintaining neans open until the predetermined minimum vehicle:peed such for example as, 25 m.p.h. has been reached, ollowing which amanual button B can become effective 0 activate the speed maintainingsystem.

A further and more specific feature of this invention s the provision ofa speed control device as aforesaid, hat is operable upon exceeding apredetermined vehicle .peed through the operation of an electricalcircuit proided with a manually actuated relay means and aunilirectional current flow means preventing a reverse curent flow thatwould otherwise leave the relay means in he closed circuit position whenit is desired to terminate he operation of the speed control device, allof which vill be described in detail hereinafter.

Referring now, in greater detail, to the figures of the lrawing, andmore particularly to FIGS. 1-3, the present mproved speed control ormanually selectable autonatic speed maintaining device is indicatedgenerally tt 2 and essentially includes an input shaft or drive means 4adapted to be connected in driving relation vith a speedometer cable 6leading to the usual drive ine transmission, and thence to the vehicledriven Wheels, ndicated schematically in FIG. 2. The speed control de-'ice 2 comprises essentially the electrical current gen- :rator G andassociated manually adjustable rheostat The generator G includes areaction stator S effective 0 make and break a speed control circuitindicated gen: :rally at 20, which includes a solenoid valve 22 forconrolIing an atmospheric engine manifold pressure supply neans 25. Thecircuit 20 is connected with a brake :ircuit 24 to provide a safetyinterlock therewith.

The drive shaft 4 is connected through gear 26 meshng with a gear 28mounted on output shaft 30 in turn wnnected with cable or like means 31extending to he vehicle speedometer-odometer instrument panel (not:hown). The input shaft 4 is connected in driving reation with armatureA, or 12 having an electrical core [Ed electric winding 32 thereabout.The rotation of I he armature A or 12 causes winding 32 to cut across helines of the magnetic field of permanent magnet M ?orming part of thegenerator G. The generator magnet tCtS upon the armature .A or 12 toinduce an opposing :lectromagnetic field and an electric current in thewindng 32. The permanent magnet M is mounted in the 'eaction statormeans S which is in the form of a housng or casing surrounding thearmature A or 12. The relCtlOll housing S is journalled for limitedarcuate movenent on armature shaft 29a which is connected with nputshaft 4, which shaft is rotatively journalled in Jearing 38a of theoutside casing 38. The effect of the )pposing magnetic fields is tocause arcuate movement or :artial rotation of the stator S in thedirection of ro- :ation of the shaft 4 and armature A or 12. The input1nd output shafts 4, 30 are rotatively journalled in ixed outer housing38 and the gears 26, 28 and stator and rotor elements A are enclosed inthe housing 5 8 which may be attached to the vehicle instrument panel[not shown).

In the more specific aspect of the present invention neans is providedfor oscillating contact C2 relative :0 C1 at a rate related to the rpm.of input shaft 4, which has been found to improve the smoothness of :heoperation of the manifold pressure supply means 25 and thus in turnoperate the engine more smoothly :han were contact C2 maintainedstationary.

Eccentric [or wobble means E] modulating means E includes a cam 42driven by the input shaft 4. Referring to FIGS. 2 and 2a, the centralaxis of rotation of the shafts 4 and 29a lie along line CC wherea s thecentral axis of the cam element 42 lies along line EE, to establisheccentricity of the cam 42 upon rotating of shaft 4. The cam 42 engagesthe arms 44 and 46 alternately of the yoke element or contact member 48which is pivotally connected by pin 50 to the housing 38. The camelement 4-2 engaging the inner sides 44a and 46a of the arms '44 and 46respectively causes the yoke element 48 to develop a small amplitude andoscillate back and forth about the pivot pin 50 and carries contact C2of arm 46 toward and away from the contact C1. The radially extendingend portion 60 of an arcuately-shaped arm 62 carries the contact C1. Thearm 62 is fastened to the crescent-shaped arm 64 by screws 66a. The arm64 has a terminal 68, contacting piston 70 urged against the terminal 68by braking spring N, held by retainer 74 mounted in the housing 38 [byscrews 66]. The arm 64 is fastened to the housing or stator S by screws66. The reaction means S, the cam element 42 and the contact arms 48 and62 are shown schematically in FIG. 1.

The rheostat means R has an electrical connection with the winding 32 ofthe electrical rotor A or 12 by way of wire 76, brushes 77, commutator79 and wire 78. The rheostat R includes a variable ohmic resistorelement 80 for controlling the value of current delivery and hence theelectrical magnetic intensity of the field developed by the rotation ofthe rotor core 32. The resistor element 80 has an indicator arm 82operable with reference to indicia in the form of miles per hour placedon suitable dial marked m.p.h. to correlate vehicular speed of thesetting of the arm 82 with corresponding values of resistance. Therheostat resistance element 80 is connected by ground wire 83 to a [pairof] first set of relay contacts [86] 86a, [86] 86b, the latter beingoperable in closed circuit position to complete a current flow paththrough the generator armature A [to open and closed circuit positionsby]. When the vehicle ignition switch 85 is opened, the contacts 86a,86b are opened, thereby making the speed control inoperative when theignition switch is open.

The electrical circuit 20 is additionally provided with an electricalrelay means 88 which includes an electromagnetic core 90 and winding 91thereabout and in addition to the foregoing first set of relay contacts86a, 86b, a second set of relay [points] contacts 88a and 88b. [Thepoints or contacts 88a, 88b are placed in open and closed circuitpositions by the operation of ignition switch 85. Electric wire 92connects the relay means with the vehicle battery 97a. A manuallyoperable button B in wire 94 of circuit 20 has an open and a closedposition and in the closed position energizes the relay means 88 tocondition circuit 20 'for being closed upon the vehicle attaining apre-selected minimum speed]. The relay 88 is prepared for energizationupon closing of igntion switch 95. Thereafter manual operation of anormally open switch B, sets the stage for energization of relay means88, when the vehicle attains a preselected minimum speed, as explainedsubsequently. The response of the relay 88 to energization is to pull-incontacts 86a, 86b, and 88a, 88b. The energization circuit for the relayincludes battery 97a, ignition switch 85, manual switch B, a diode 93,and relay coil 88. A holding circuit for coil 88, once the latter isenergized, includes a wire 92, closed contacts 88a, 88b, wire 94,. diode93 and coil 88. [A] The unidirectional current flow means [in the formof a diode], herein illustrated as the diode 93 between line [4] 94 andrelay means 88, allows current to flow to the relay means, but preventsreverse current flow [in reverse direction] from the brake circuit 24[relay means to wire 94, which in turn connects with contact C2].

The brakecircuit '24 containing the usual signal light is completed bydepressing the brake pedal 24a to operate brake switch 96. This circuitincludes wire 97 going from a source of electrical power, which in thiinstance is the battery 97a, to ground 97b, and a wire 98 connectingcircuits 24 and 20 through centrifugal switch means 99. The switch means99 includes the pair of electrical contact points C3, C4 and acentrifugal weight 9%., as shown schematically in FIG. 1, whereby thecentrifugal weight 99a is connected with and operated in response to theacceleration of the vehicle and allows the contact C3 to engage contactC4, thu completing the electrical circuit 20 connecting line 98 withline 100, thereby conditioning relay 88 for operation. Line 101[contacts] connects contact C1 with solenoid 22 having ground wire 101a.The completing of this part of the circuit through the centrifugalswitch is arranged to occur at any selected speed, such as 25 m.p.h.

'Fhe solenoid valve means 22 comprises a valve housing 102 in which isdisposed an electromagnetic solenoid 103 for raising a plunger 104having a valve head 105 urged to seat 106 by spring 107. Engine manifoldvacuum pressure i.e., a pressure below atmospheric pressure that existswithin the engine manifold, is admitted into the valve housing passage108. Line 110 admits the atmosphere to the solenoid means 22, conduit112 connects the passage 10!! with the engine manifold line 114 belowthe butterfly valve 116 which constitutes the engine throttle means. Thethrottle means or butterfly valve 116 is connected with the vehicleaccelerator pedal 118 by a suitable linkage 120. A chain 122 connectslinkage 120 with bellows portion 124 of a bellows servomotor 126, thebutterfly valve 116 being urged to a closed position by a spring 128.The servomotor unit include a spring 130 that urges the bellows to anextended position. The servomotor 126 is connected through chain 122with linkage 120 on one side and on the other side with support 134. Apassage 136 communicates between the valve housing outlet "13-8 and theinlet of the chamber 140 of the bellows portion of the servomotor.

OPERATION As the vehicular road speed i increased, the speedometer cablecauses rotation of the input shaft 4 and armature A or 12 whereby anelectrical current is generated through the magnetic field of thewinding of the rotor or armature A or 12 crossing the field of thepermanent magnet M. This causes the stator S to rotate in the samedirection as the rotation of the input shaft 4 (see arrows FIGS. 1, 2and 3). The intensity of the field developed and therefore the torquedelivered to the reaction housing or stator S is determined by thesetting of the rheostat R. The greater the electrical resistance of therheostat-depending upon the speed setting-the greater the speed requiredto generate the value of electrical current flow through the selectedresistance of the rheostat for operation of the solenoid [value] valve22.

Now with reference to FIG. 3 it will be seen that the generator arm 64is normally urged by the spring [72] N to place the first contact C1into engagement with the second contact C2. The reaction torque causingthe arcuate movement [of] or partial rotation of the stator S throughthe influence of the magnetic field tends to rotate the stator orhousing S and the arm 64 in a counterclockwise direction, thusovercoming the opposing action of spring N to thus cause the contact C1to separate from contact C2. Upon increase of the road load of thevehicle upon encountering an increased grade, the angular velocity ofthe speedometer shaft 4 will decrease and therefore the torque deliveredto the generator reaction housing S will decrease and the spring N willforce the arm 68 of the generator reaction housing S clockwise causingcontacts C1 and C2 into contact, completing circuit and again energizingsolenoid valve 22 producing an increase in engine speed. The rheostatunit [12] R through its ohmic resistance value setting corresponding tothe selected speed determines the intensity of the magnetic cfield andtherefore the torque applied to the generator housing. The greater theresistance setting of rheostat R, the lesser the tendency of reactionhousing 8 to rotate against the spring N for a given speed. The ohmicresistance setting is proportional to the speed of the vehicle to bemaintained. At high ohmic resistance values, say at m.p.h. speedometerreading, the resistances are correspondingly high and therefore theability of the generator reaction housing to rotate is correspondinglylimited and the more eifective the spring tending to maintain contactsC1 and C2 closed, and cause the engine to operate at higher speeds. Atlower ohmic resistance values, the reverse is true, i.e., the torque ofthe generator housing opposing the force of the housing spring isobtained at a lower rotational speed so that the engine operates at acorrespondingly lower speed.

Only at speeds in excess of 20-25 m.p.h. will the rotation of the outputshaft cause the centrifugal switch means C3 and C4 to complete thecircuit 20. The manually operated button [85] B may then be depressed tocomplete the circuit and cause the relay unit 88 to maintain thecontacts 86a, 86b and therefore C1 and C2 in the closed positionprovided the vehicle is below set speed. This condition energizes thesolenoid means 22 to retract plunger 104 and the solenoid valve 105blocks communication between the atmospheric line and the line 136leading to the diaphragm unit 126 and permit manifold vacuum pressure tobe admitted to the servomotor unit 126 allowing the bellows 124 tocontract and pull onthe ohain 122 to open the throttle or butterflyvalve 116 to the atmosphere, resulting in an increase in engine speed.When the contacts C1 and C2 are opened the solenoid valve becomesdeenergized (see FIG. 1) so that the atmosphere is allowed tocommunicate with the diaphragm and the manifold pressure is blockedfromthe diaphragm unit 126 so that the diaphragm unit is allowed toexpand, causing a relaxing of the pull through chain 122 and allowingthe spring 128 to close the butterfly valve 116 with a resultingdecrease in engine speed.

It will thus be seen that depending upon the desired speed as determinedby the setting of the rheostat unit [14] R readable in miles per hourthe desired output speed will be maintained. Should the [ouput] outputspeed decrease, the contacts C1 and C2 will complete the circuit 20 andthe throttle means 116 will be opened to increase the engine speed.Whereas, when the output speed increases beyond the selected value thecontacts C1 and C2 will separate, opening the circuit 20 with the resultthat the throttle valve is closed and the engine speed thus decreased.

Modulating means introducing a predetermined frequency in thepositioning of [contacts] contact C2 for engagement with contact C1 isprovided in the form of the eccentric cam element 42 (FIG. 2a) which isslightly off center from the central axis C-C of the input shaft 4causing the contact C2 to oscillate, resulting in a gradual net circuitopening or circuit closing effect in the operation of the contacts C1and C2. This results in a smoother gradual transition of engine speedchanges and eliminates jerking or hunting of the engine in response toincrease or decrease of road loads thereon as when grade changes areencountered.

The modulating means controls the effective strength and duration of thecontrol signals delivered to solenoid valve 22 within a range of :3m.p.h. to prevent hunting. When energizing the system below the setspeed, the energy transferred from the armature A is not sufficient toarcuately move the reaction member S against the spring [72] N, therebymaintaining the contacts C1 and C2 closed. When the vehicle speedreaches 3 m.p.h. in excess of the predetermined or reference speed, thereaction member exerts suificient force to separate contact C1 fromcontact C2 against the action of the spring [72] N momentarily,interrupting the current supplied to the solenoid means 22 venting theservomotor 126 to atmosphere when off and to vacuum when the contactsare momentarily closed. The ratio of off to on times deter- 7 nines theamount of vacuum transmitted to the diaphragm lnit or servomotor 126.

The brake light switch provides a safety measure. If it s desired to gooff the automatic speed control, i.e., renove the speed control device[from] for normal driving, me merely has to depress the brake pedal ofthe vehicle vhich completes the brake light circuit 24- and the brakeight goes on. At the same time the brake light circuit lelivers acountering voltage to the relay means 88 by vay of line 97 which is thusde-energized by the voltage applied through line 92, since there nowexists no po- :ential difference across the relay means 88 and the:ircuit 20 is thus opened. The circuit 20 can be closed again only bydepression of the manual button B subseuent to the release of the brakepedal 24a.

FIG. 4 illustrates a modified form of means for operat- .ng the contactsC1 and C2, also described in connection with FIGS. 1 through 3 and thesame reference characters are used in this modified form where thestructures correspond. Referring now to FIG. 4, there is shown a yoke orbifurcated element 48 pivoted on the pin 150 and :arrying an electricalcontact C2. Further, there is provided an arm 142 that is also mountedon the pin 50 and has an arcuate portion 144 extending partially aroundthe :am element 42 between a portion 146 connected to the pin 150 and afree end portion 148 carrying the usual electrical contact C1. Thespring N has one terminal connected to the housing 38 by pin 152 and theother terminal connected with the free end 148 for urging contact C1into engagement with contact C2. The reaction housing S is provided atits outer periphery with a pin 154 for engaging with the tip 156 of thearm 142. The pin 154 when rotating in a counterclockwise direction, willcause separation of the contacts C1 and C2 against the action of thespring [N] N,.

While contacts C3 and C4 are shown and described as being operated bycentrifugally responsive weight means, it will be apparent that othermeans, such as an electromagnet, could be employed to operate thesecontacts as a function of speed in any well known manner.

While only certain preferred embodiments of the invention have beendescribed and illustrated, it is apparent that other modifications andalterations may be made therein. [It is therefore intended in theappended claims to cover all such modifications and alterations as mayfall within the true spirit and scope of the invention consistent withthe state of the prior -art.]

It will be appreciated that the electrical circuit 20 and the electricalcontacts C1 and C2, and the solenoid valve 22 may be replaced by anysuitable mechanical linkage connecting the stator S with a pneumaticvalve for selectively venting atmosphere pressure and manifold vacuumpressure to the servomotor 26. However, the preferred form is to employthe contacts C1 and C2 as shown by the present disclosure, since in themore specific aspects of the present invention it has been found thatunusually satisfactory results are obtained by this construction. I

It will also be appreciated that the spring N may be replaced by anelectrical power means such as a battery source connected with the lead83 (rather than having the lead 83 go to ground, as shown) whereby thebattery would supply a counter electromotive force opposing the voltagegenerated by the generator G. However, the preferred form is to employthe spring N as shown by the present disclosure, since in the morespecific aspects of the present invention it has been found thatunusually satisfactory results are obtained by this construction.

What is claimed is:

'1. In an automatically operable, manually selectable, speed maintainingdevice particularly adapted for the prime mover of a ground vehicle,said device including means for sensing the ground speed of the vehicle,means including an armature arranged to be driven by said speed sensingmeans efiective to generate a varying magnetic field in proportion tosaid speed, a magnet reaction means automatically arcuately movable inproportion to the intensity of said magnetic field, electrical contactmeans, a means defining a control circuit containing said contact means,said reaction means being operably responsive to a predetermined valueof said magnetic field eifective to operate said contact means,resistance means in said circuit for regulating the value of the currentdelivered to said armature as a function of the desired vehicle speed tobe maintained and hence the intensity of said magnetic fieldcorrespondingly determining the extent of arcuate movement of saidreaction means in relation to a predetermined vehicle speed, saidresistance means providing a resistance to the current flow to saidarmature and hence the intensity of said magnetic field generated, andmeans in said circuit to regulate the fuel delivery to said prime mover,said contact means being operative in open and closed positions of saidcontacts to increase and decrease the vehicle speed.

2. In an automatically operable, manually selectable, speed maintainingdevice particularly adapted for the prime mover of a ground vehicle,said device including means for sensing the ground speed of the vehicle,means including an armature arranged to be driven by said speed sensingmeans effective to generate a varying magnetic field in proportion tosaid speed, magnetically conductive means automatically arcuatelymovable in proportion to the intensity of said magnetic field,electrical contact means, a means defining a control circuit containingsaid contact means, said magnetically conductive means being operablyresponsive to a predetermined value of said magneticfield effective tooperate said contact means, manually adjustable resistance means in saidcircuit for regulating the value of the current delivered to saidarmature as a function of the desired vehicle speed to be maintained andhence the intensity of said magnetic lfield correspondingly determiningthe extent of arcuate movement of said magnetically conductive means inrelation to a predetermined vehicle speed, said resistance meansproviding a resistance to the current flow to said armature and hencethe intensity of said magnetic field generated, and means in saidcircuit to regulate the fuel delivery to said prime mover, said contactmeans being operative in open and closed position of said contacts toincrease and decrease the vehicle speed.

3. In an automatically operable, manually selectable, speed maintainingdevice particularly adapted for the prime mover of a ground vehicle,said device including means for sensing the ground speed of the vehicle,means including an armature arranged to be driven by said speed sensingmeans effective to generate a varying magnetic field in proportion tosaid speed, a magnet reaction means automatically arcuately movable inproportion to the intensity of said magnetic field, means for increasingand decreasing the supply of fuel to the prime mover for increasing anddecreasing the speed of the vehicle, said reaction means being operablyresponsive to a predetermined value of said magnetic field effective tooperate said means for increasing and decreasing of the fuel, resistancemeans in said circuit for regulating the value of the current deliveredto said armature as a function of the desired vehicle speed to bemaintained and hence the intensity of said magnetic fieldcorrespondingly determining the extent of arcuate movement of saidmagnetically conductive means in relation to a predetermined vehiclespeed to increase and decrease the vehicle speed.

4. In a manually selectable automatically operable vehicle speedmaintaining device adapted for a prime mover having a servomotoroperated means for adjustably feeding fuel thereto, vehicle speedsensing means, means in combination with said fuel feeding means andsaid speed sensing means effective to adjust the rate of fuel deliveryto said prime mover for maintaining a selected constant speed of saidvehicle irrespective of variations in the grade of the surface overwhich the said vehicle is being driven, said last named means includingmeans defining an electrical field generator having an armature adaptedto be driven by said speed sensing means, and a reaction stator, thelatter being arranged for limited arcuate movement, means opposedlyadjusting the torque reaction of said arcuately adjustable stator inproportion to the intensity of the field generated by said generator,means defining a pair of electrical contacts, one of which is movablewith reference to the other in response to the arcuate adjustment ofsaid stator against the said action of said means opposedly foroperating said contacts in response to the generation of a predeterminedfield intensity by said generator, manually selectable speed settingmeans comprising an electrical resistance means having a plurality ofsettings corresponding to respective selectable speeds to be maintainedconstant, circuit defining means placing the armature of said generatorand said rheostat in series relation, current supply defining means forsupplying current to said resistance means whereby when said selectedspeed has been reached, said generator will produce a torque reaction onsaid stator of a magnitude to cause an opening of said contacts, meansfor automatically operating said servomotor including a solenoid valveeffective to selectively deliver manfold vacuum or atmospheric pressureto said adjustable fuel delivery servomotor means and to effect eitheropening or closing of said valve, and means defining a control circuitfor said solenoid under the control of said generator stator reactionoperated contacts.

5. In a device for automatically maintaining a manually selected speedof a vehicle driven by an internal combustion engine and comprising,means elfective to produce a rotating magnetic field having an intensitycorresponding to said manually selected vehicle speed, magneticallyresponsive torque reaction means positioned for movement under theinfiuence of said rotating magnetic field, means yieldably resistingsaid movement, an electrical circuit comprising a pair of electricalcontacts, means biasing one of said contacts with respect to the other,means driven by said magnetically reactive means effective to move oneof said contacts against said biasing means and with respect to theother contact upon the occurrence of a predetermined torque reaction insaid magnetically responsive torque reaction means, speed regulatingmeans in the form of a manually settable resistance means having valuesrepresenting given vehicle speeds and in electrical connection with saidfirst mentioned means, servomotor means, said electrical circuitcomprising a solenoid valve selectively supplying engine manifold andatmosphere pressures to said servomotor during open.and closed circuitpositions, engine throttle means, and linkage connecting the servomotormeans with the throttle means whereby said throttle means is opened andclosed by the solenoid means.

6. A speed control device for a vehicle having a prime mover, saiddevice comprising speed sensing means on the vehicle, means forproducing a magnetic field moving at a rate which is related to the rateof movement of the speed sensing means and operatively connectedtherewith, magnetically conductive means positioned for movement underthe influence of said moving magnetic field, an electrical circuithaving a pair of electrical contacts, means opposing the movement ofsaid magnetically conductive means for positioning one of said contactswith respect to the other, means carried by said magnetically conductivemeans and operable to oppose the positioning of said one contact,manually adjustable means for regulating the level of the magnetic fieldto thereby correspondingly regulate the extent of the movement of saidmagnetically conductive means in accordance with a desired vehicle speedand electrically connected with said means for producing a magneticfield, and means in said circuit regulating the fuel de- 10 livery tosaid prime mover and operative to increase and decrease the vehiclespeed.

7. In an automatic, manually selectable speed maintaining control deviceadapted for a vehicle including a prime mover, rotatable vehicle speedsensing means, an electric means effective to produce a rotatingmagnetic field as a function of the rate of rotation of said speedsensing means and adapted to be drivingly connected therewith, torquereactive magnetic means responsive to said rotating magnetic field,including means defining an electrical circuit having a pair ofelectrical contacts therein, said torque reactive means being elfectiveto operate one of said contacts from closed to open circuit, manuallyadjustable means for regulating the intensity of said magnetic field tothereby correspondingly regulate the extent of arcuate movement of saidmagnetically reactive means in accordance with a predetermined vehlclespeed and electrically connected with said means for producing saidmagnetic field, said manually adjusta-ble means being related to aselected set speed control providing a resistance to said electric meansfor in turn producing an adjustable magnetic field, and means in saidcircuit adapted to regulate the fuel delivery to said prime mover, saidmeans being operative to increase and to decrease the vehicle speed.

8. In an automatic, manually selectable speed mainta ning control deviceadapted for a vehicle including a P111116 mover, rotatable vehicle speedsensing means, an electric means effective to produce a rotatingmagnetic field as a function of the rate of rotation of said speedsensing means and adapted to be drivingly connected therewith, torquereactive magnetic means responsive to said rotating magnetic field,including means defining an electrical circuit having a pair of electriccontacts therein, said torque reactive means being effective to operateone of said contacts between open and closed circuit positions, manuallyadjustable means for regulating the intensity of sa1d magnetic field tothereby correspondingly regulate the extent of arcuate movement of saidmagnetically reactive means in accordance with a predetermined vehiclespeed and electrically connected with said means for producing saidmagnetic field, said manually adjustable means being related to aselected set speed control providing a resistance to the currentproduced by said electric means for in turn producing an adjustablemagnetic field, and means in said circuit adapted to regulate the fueldelivery to said prime mover, said means :being operative to increaseand decrease the vehicle speed.

9. The invention according to claim 8 wherein said electrical circuit isprovided with an electrical valve means arranged to be alternativelyplaced in operative connection with engine manifold pressure andatmospheric pressure, a pressure responsive servomotor, an enginethrottle means operatively connected with said servomotor and with anaccelerator and movable in accordance therewith, whereby atmosphericpressure and manifold pressure is selectively communicated past thesolenoid valve to the servomotor to operate the throttle means.

10. The invention according to claim 8 wherein said electrical circuitcomprises a relay means including an electrical valve means and manuallyoperated switch having a closed circuitposition for energizing saidvalve means, and contact means energized by said valve means foroperating the electrical circuit.

11. An electrically operated speed control device for adjustablecontrolling the speed of operation of a prime mover, said devicecomprising speed sensing means, means for producing a magnetic fieldmoving at a rate which is related to the movement of the speed sensingmeans and operatively connected therewith, magnetically conductivetorque reaction responsive means positioned for limited movement underthe influence of said moving magnetic field, an electrical circuithaving a pair of electrical contacts, means for moving one of saidcontacts relative to the other in one direction, means carried by saidmagnetically conductive reaction means and operable to move of saidcontacts in the opposite direction of said one contact, adjustable meansfor regulating the level of the magnetic field and therebycorrespondingly regulate the extent of the movement of said magneticallyconductive means in accordance with a desired speed and electricallyconnected with said means for producing said magnetic field, and meansin said circuit regulating the fuel delivery to said prime mover andoperative by said contacts to increase and decrease the speed of theprime mover.

12. An electrical speed control device for selectively controlling thespeed of operation of a prime mover adapted to be driven by a vehiclespeed sensing means, said device comprising an electric generator meanshaving a rotor element in driving connection with said speed sensingmeans and having a torque reaction magnet stator circumscribing saidrotor, said rotor having an electricalwinding effective to produce amagnetic field for inducing a reaction in the field of said magnetstator for causing limited rotation of said stator, current adjustingmeans electrically connected with said rotor providing a resistanceadjustable in accordance with a desired selected prime mover speed forcontrolling the degree of rotation of the rotatable stator, anelectrical circuit having a 'pair of electrical contacts, biasing meansurging one of said contacts in one direction relative to the othercontact for circuit operation, abutment means carried by said rotatablemember and operable to move one of said con-tacts in the oppositedirection relative to the other contact for circuit operation, in anarcuate path determined by the setting of said current adjusting meansregulating the intensity of the magnetic field in accordance with adesired prime mover speed, and means in said circuit regulatnig the fuelsupply to said prime mover and operative by the contacts to increase anddecrease in the speed of the prime mover.

13. The invention according to claim 12 wherein said respective contactshaving supporting means movable about a common pivot independent of thertoatable stator and pivotal toward and away from one another, saidbiasing means for said one contact including spring means urging saidone contact relative to the other said contact, said rotatable statorbeing provided with an extension engageable with said first contacteffective to move it in opposition to said spring means.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 2,181,429 11/1939 Hansen 82.1 2,643,871 6/1953Warrick 73540 2,920,154 1/ 1960 Allen 20061.46X 3,062,312 11/1962Dietrich et al. 18082.1 3,088,538 5/1963 Brennan et a1 123102X 3,216,52211/1965 Cassano ISO-82.1

A. HARRY LEVY, Primary Examiner US. Cl. X.R. 1231 02; 180110

